The present invention relates to reactive dye compounds. In particular the present invention relates to reactive dye compounds having improved dye-bath Exhaustion (E) and improved dye-fibre covalent Fixation (F).
Reactive dye compounds are known in the art for dyeing various substrates. Such substrates include for example proteinaceous materials such as keratin, e.g. found in hair, skin and nails and various animal body parts such as horns, hooves and feathers, and other naturally occurring protein containing materials, e.g. silk and saccharide-derived materials such as those derived from cellulose or cellulose derivatives, e.g. natural products such as cotton, and synthetic fibres such as polyamides.
Examples of classes of such reactive dyes which are well known in the art include dyes containing a mono- or dichloro- or fluoro-1,3,5-triazinyl group, trichloro or mono- or di-fluoro-pyrimidyl group, beta-halogen-propionyl group, beta-halogenoethyl-sulphonyl group, beta-halogenoethylsulphamyl group, chloroacetyl amino, beta-(chloro-methyl)-beta-sulphatoethylsulphamyl group, or a vinyl sulphonyl group.
In the case of the dyes containing a triazinyl group or a pyrimidyl group, in place of the reactive halogen atoms one can use other groups which dissociate in the presence of alkali. Canadian Patent 771632, for example, discloses examples of such other groups including sulphonic acid, thiocyanate, sulphophenoxy, sulphophenyl thio, nitrosulphophenoxy groups, and quaternary ammonium groups.
xe2x80x9cThe Synthesis and Properties of some Triazine-Stilbene Fluorescent Brightenersxe2x80x9d, I. Grabtchev, discloses the synthesis of certain triazine stilbene fluorescent brighteners containing methacrylic groups.
The Journal of Macromoleular Chemistry 64 (1977), 205-210 (Nr. 951) discloses the polymerisation of acrylonitrile in dimethylformamide in the presence of some unsaturated triazine derivatives. The Journal of Macromolecular Chemistry 50 (1976) 1-8 (Nr.728) discloses the polymerization of styrene in the presence of some coloured anthraquinone and azoderivatives of 1,3,5-triazine, containing a group able to copolymerize.
The Journal of the Chemical Society, 1963, pages 4130-4144, xe2x80x9cThe Hydrolysis of Some Chloro-1,3,5-Triazinesxe2x80x9d by S. Horrobin, discloses that dichloro-m-sulphoanilinotriazine is rapidly hydrolysed in acetate (pH 4.7) or phthalate (pH 4.0) buffers.
There are many different types of commercially-available reactive dyes for dyeing cellulosic and polyamide-type substrates. However, a critical problem still facing the textile dye industry today is the significant level of dyestuff material which remains in the effluent waste water after the dyeing process is finished. The industry measure for this problem is known as dye-bath Exhaustion (E). A high Exhaustion value for a particular dye compound means that a low level of spent dye remains in the effluent after the dyeing process is complete, while a low Exhaustion value means that a high level of spent dye remains in the effluent. There is clearly a need therefore for new dye compounds which have higher Exhaustion Values compared with commercially available dye compounds, and which provide benefits in terms of reducing levels of spent dyestuff in effluent water.
As well as having a high Exhaustion Value, it is also important for a dye compound to have a high dye-fibre covalent Fixation Value (F). The Fixation Value (F) of a reactive dye compound is a measure of the extent of covalent bonding with the substrate based on the dye originally absorbed during the dyeing process. Thus 100% Fixation means that 100% of the absorbed dye covalently bonds to the substrate. Thus, there is clearly a need to provide dye compounds having increased Fixation Values. A high Fixation Value can result in a simplification of the post dyeing xe2x80x9csoaping off processxe2x80x9d traditionally associated with fibre reactive dye compounds. In particular, a high Fixation Value can result in a reduced time spent on the xe2x80x9csoaping off processxe2x80x9d together with a reduced cost.
It has now been surprisingly found that a new class of fibre reactive dye compounds comprising a nitrogen-containing heterocycle substituted with at least one oxy carbonyl derivative, such as citrate, exhibit significantly increased values of Exhaustion (E) and Fixation (F). These dyes can be used on a wide variety of substrates. They are particularly useful for cellulosic substrates, such as cotton, and materials such as keratin, hair, wool and silk, and show significant improvements in terms of reducing spent dyestuff in effluent, increasing dye affinity to the substrate, increasing the efficiency of the dye-substrate covalent reaction, and simplifying the post dyeing xe2x80x9csoaping off processxe2x80x9d traditionally associated with reactive dyes. In addition, the compounds of the present invention provide significantly more intense dyeings, and can be used for both high and low temperature dyeing, hence reducing the cost of the dyeing process. Furthermore, the compounds of the present invention can be used together with specific chromophores for cellulose substrate dyeing leading to significantly reduced levels of salt needed for dyeing.
According to the present invention there is provided a reactive dye compound comprising:
(a) at least one chromophoric moiety;
(b) at least one nitrogen-containing heterocycle;
(c) a linking group to link each chromophoric moiety to each nitrogen-containing heterocycle;
characterised in that at least one nitrogen-containing heterocycle is substituted with at least one oxy- or thio-carbonyl derivative wherein the oxy- or thio-carbonyl derivative is selected from Y wherein Y is xe2x80x94A(CO)R* wherein A is selected from O or S, where R* is an organic residue which contains at least one nucleophilic group, wherein the nucleophilic group is preferably selected from OH, NH2, SH, COOH, xe2x80x94Nxe2x95x90, NHR1 and NR1R2 wherein R1 and R2 may be the same of different and may be selected from C1-C4 alkyl.
The compounds of the present invention exhibit increased Exhaustion (E) and Fixation (F) values and provide improvements in terms of reducing spent dyestuff in effluent, increasing dye affinity to the substrate, increasing the efficiency of the dye-substrate covalent reaction, ability to carry out the long-liquor dyeing process at room temperature as well as at elevated temperatures, and simplifying the post dyeing xe2x80x9csoaping off processxe2x80x9d traditionally associated with fibre reactive dyes. In addition, the compounds of the present invention provide significantly more intense dyeings, i.e. greater colour intensity in the dyed substrate, without compromising levelness.
As used herein the term xe2x80x9creactive dyexe2x80x9d means a dye containing one or more reactive groups, capable of forming covalent bonds with the substrate to be dyed, or a dye which forms such a reactive group in situ.
As used herein the term xe2x80x9cExhaustionxe2x80x9d in relation to reactive dyes means the percentage of dye which is transferred from a solution of the dye to the substrate to be treated at the end of the dyeing process, before rinsing and soaping. Thus 100% Exhaustion means that 100% of the dye is transferred from the dye solution to the substrate. Typical Exhaustion Values for the dye compounds herein are  greater than 95%.
As used herein the term xe2x80x9cFixationxe2x80x9d in relation to reactive dyes means the percentage of dye which covalently bonds with the substrate, based on the dye originally absorbed during the dyeing process. Thus 100% Fixation means that 100% of the dye absorbed is covalently bonded with the substrate. Typical Fixation Values for the dye compounds herein are 95%.
The total efficiency of reactive dyes can be measured by their Efficiency Value (T) which can be calculated from the Exhaustion Value (E) and Fixation Value (F) using the following equation:
%T=(Fxc3x97E)/100
The compounds of the present invention comprise a chromophoric moiety and a nitrogen-containing heterocycle linked via a linking group. The nitrogen-containing heterocycle is substituted by at least one oxy- or thio-carbonyl derivative xe2x80x94A(Cxe2x95x90O)R* wherein A is selected from O or S, and R* is an organic residue which comprises at least one nucleophilic group, wherein the nucleophilic group is preferably selected from OH, NH2, SH, COOH, xe2x80x94Nxe2x95x90, NHR1 and NR1R2 wherein R1 and R2 may be the same or different and may be selected from C1-C4 alkyl.
The reactive dye compounds herein can comprise one or more chromophoric moieties (D or Dxe2x80x2). In reactive dye compounds comprising two or more chromophoric moieties these can be the same or different. Preferably the reactive dye compounds herein comprise from one to three chromophoric moieties.
Any chromophoric moieties suitable for use for dyeing substrates can be used in the present invention. The term chromophore as used herein means any photoactive compound and includes any coloured or non-coloured light absorbing species, eg. fluorescent brighteners, UV absorbers, IR absorbing dyes.
Suitable chromophoric moieties for use in the dye compounds herein include the radicals of monoazo, disazo or polyazo dyes or of heavy metal complex azo dye derived therefrom or of an anthraquinone, phthalocyanine, formazan, azomethine, dioxazine, phenazine, stilbene, triphenylmethane, xanthene, thioxanthene, nitroaryl, naphthoquinone, pyrenequinone or perylenetetracarbimide dye.
Suitable chromophoric moieties for use in the dye compounds herein include those disclosed in EP-A-0,735,107 (Ciba-Geigy), incorporated herein by reference, including the radicals described therein which contain substituents customary for organic dyes, such as sulphonate substituents which enhance the water-soluble properties of the dye compound.
Most preferred chromophoric D or Dxe2x80x2 groups for use herein are polysulphonated azo chromophores such as those present in Procion (RTM) dyes commercially available from BASF, Drimalan (RTM) dyes commercially available from Clariant, Drimarene (RTM) dyes commercially available from Clariant and Levafix (RTM) dyes commercially available from Dystar.
The reactive dyes of the present invention comprise at least one nitrogen-containing heterocyclic moiety. In reactive dye compounds containing two or more nitrogen-containing heterocycles these can be the same or different. Preferably the reactive dye compounds herein comprise from one to three nitrogen-containing heterocycles. At least one of the nitrogen-containing heterocycle moieties herein is substituted with at least one oxy- or thio-carbonyl derivative.
Suitable nitrogen-containing heterocycles for use herein include monocyclic, bicyclic or polycyclic, unsaturated heterocycles containing at least one nitrogen heteroatom. When monocyclic rings are used, they are preferably selected from unsaturated rings having from about 3 to about 7 ring atoms, especially 5 or 6 ring atoms, comprising from about 1 to about 3 nitrogen heteroatoms, preferably 2 or 3 nitrogen heteroatoms. When bicyclic heterocycles are used, they preferably comprise an unsaturated nitrogen containing heterocycle having 3 to 7 ring atoms, preferably an unsaturated nitrogen containing heterocycle having 5 or 6 ring atoms comprising 1 or 2 nitrogen atoms, fused to a 5 to 7 membered carbocycle preferably a 6-membered unsaturated carbocycle. When bicyclic heterocycles are used, the oxy- or thio-carbonyl substituents are preferably attached to the nitrogen-containing heterocyclic ring.
Preferred for use herein are 5 or 6 membered unsaturated nitrogen-containing monocyclic heterocyclic rings comprising 2 or 3 nitrogen heteroatoms or bicyclic rings containing a 5 or 6 membered unsaturated heterocyclic ring containing 2 nitrogen heteroatom fused to a 6 membered unsaturated carbocycle.
Examples of suitable heterocycles for use herein include, but are not necessarily limited to triazine, pyrimidine, quinoxaline, pyrimidinone, phthalazine, pyridazone and pyrazine.
Preferred for use in the compounds herein are triazine, pyrimidine and quinoxaline.
The compounds herein further comprise a linking moiety to link each nitrogen-containing heterocycle to each chromophoric moiety. Any linking moieties suitable for use in dyeing substrates can be used in the present invention. Preferably the linking moiety is selected from NR, NRCxe2x95x90O, C(O)NR, NRSO2 and xe2x80x94SO2NR wherein R is H or C1-C4 alkyl which can be substituted by halogen, preferably fluorine or chlorine, hydroxyl, cyano, C1-C4 alkoxy, C2-C5 alkoxycarbonyl, carboxyl, sulfamoyl, sulfo or sulfato. When the heterocycle is a triazine or pyrimidine a preferred linking moiety is NR, preferably where R is H or C1-C4 alkyl, more preferably where R is H or CH3, especially H. When the heterocycle is quinoxaline or phthalazine, a preferred linking moiety is NRCxe2x95x90O, where R is H or C1-C4 alkyl, more preferably where R is H or CH3, especially H.
Suitable oxy- or thio-carbonyl derivatives for use herein are those having the formula xe2x80x94A(Cxe2x95x90O)R* wherein A is selected from OS or Se, preferably S or O, more preferably O, wherein R* is an organic residue which comprises at least one nucleophilic group. As used herein the term xe2x80x9cnucleophilic groupxe2x80x9d means a negative ion or any neutral molecule that has an unshared electron pair. Preferred nucleophilic groups herein can be selected from OH, NH2, SH, COOH, xe2x80x94Nxe2x95x90, NHR1 and NR1R2 wherein R1 and R2 may be the same or different and may be selected from C1-C4 alkyl.
Suitable R* groups for use herein are alkyl or aryl residues which contain at least one nucleophilic group. Preferably the R* groups herein are selected from the following groups each substituted with or containing at least one nucleophilic group: substituted or unsubstituted, straight chain or branched chain C1-C8 alkyl, substituted or unsubstituted straight chain or branched chain C2-C8 alkenyl having at least one olefinic group, substituted or unsubstituted, saturated or unsaturated or aromatic 3-9 atom monocyclic carbocycle or substituted or unsubstituted, saturated or unsaturated or aromatic 7-17 polycyclic carbocycle, substituted or unsubstituted, saturated or unsaturated or aromatic 3-9 atom monocyclic heterocycle or substituted or unsubstituted, saturated or unsaturated or aromatic 7-17 atom polycyclic heterocycle, wherein said heterocycles each have one or more heteroatoms selected from O, N or S.
In the definition of R* above, where the term xe2x80x9csubstitutedxe2x80x9d is used such substitution may be with one or more substituents. Such substituents include, but are not limited to, those listed in C. Hansch and A. Leo, Substituent Constants for Correlation Analysis in Chemistry and Biology (1979), hereby incorporated by reference herein. Preferred substituents include, but are not limited to, alkyl, alkenyl, alkoxy, hydroxy, oxo, amino, aminoalkyl (e.g.aminomethyl, etc.), cyano, halo, carboxy, alkoxyacetyl (e.g. carboethoxy, etc.), thio, aryl, cycloalkyl, heteroaryl, heterocycloalkyl, (e.g.piperidinyl, morpholinyl, piperazinyl, pyrrolidinyl, etc.), imino, thioxo, hydroxyalkyl, aryloxy, arylalkyl, and combinations thereof.
Preferred R* groups for use herein include, but are not limited to, CF3, (CH2)nSH, (CH2)nNH2, CH(CH3)OH, C(OH)(CH2COOH)2, CH2C(OH)(CO2H)CH2COOH, (CH2)nNHR1, CH2NR1R2, CH2NHNH2, CH2NHOH, CH2SMe, CH(NH2)(CH2)n(COOH), CH(NH2)CH2SMe, CH(NH2)CH2SSCH2CH(NH2)COOH, 2-aminophenyl, 2-hydroxynaphthyl, 2-pyrrolidyl, CH2SSCH2CO3xe2x88x92, (CH2)nxe2x80x94SO3xe2x88x92, CH(NH2)CH2SO3H, C6H4OH, C6H4COOH, C6H4NH2, C5H4NH2, (CH2)nC5H4N, CH(R#)NH2, (CH2)nxe2x80x94SSO3xe2x88x92, (CH2)nxe2x80x94Sxe2x80x94Sxe2x80x94(CH2)n, xe2x80x94C(OH)(H)COOH, xe2x80x94C(OH)(H)CH2COOH, xe2x80x94C(OH)(COOH)CH2COOH, CH2(H)(OH)COOH, derivatives of hydroxy carboxylic acid polymerisation, eg. in the case of lactic acid dimerisation R* is CH(CH3)O(CO)CH(CH3)OH, R* groups derived from peptide or polypeptide and attached to the heterocyclic group via their terminal carboxylic group, wherein R1 and R2 is independently selected from C1-C4 alkyl, wherein n is an integer in the range of 1 to 4 wherein within the same molecule n is not necessarily the same integer and where R# corresponds to an amino acid sidechain. For examples of such amino acids, cf. xe2x80x9cOrganic Chemistryxe2x80x9d by Graham Solomons, 5th Edition, Wiley, New York, 1992, p1094-1095.
Preferred R* groups for use herein are selected from (CH2)nSH, (CH2)nNH2, C5H4N, CH(CH3)OH, C(OH)(CH2COOH)2, CH(R#)NH2, CH2C(OH)(COOH)CH2COOH, CH(CH3)OH, CH(OH)CH2COOH, CH2C(H)(OH)COOH, C(H)(OH)C(H)(OH)COOH, C6H4OH, C6H4NH2 and C5H4N.
Particularly preferred R* groups herein are groups derived from hydroxy carboxylic acids such as citric acid, lactic acid, tartaric acid, malic acid, salicylic acid, and the like, including structural isomers thereof (eg. in the case of citric acid R* can be C(OH)(CH2COOH)2 and CH2C(OH)(COOH)CH2COOH) and polymers thereof (eg. in the case of polymerisation of two lactic acid molecules R* is CH(CH3)O(CO)CH(CH3)OH.
Particularly preferred R* group from the viewpoint of providing reactive dye compounds having excellent dye properties are those derived from citric acid, including C(OH)(CH2COOH)2 and CH2C(OH)(COOH)CH2COOH. It will be understood by those skilled in the art that in the case of unsymmetrical compounds having more than one carboxylic acid group, for example, citric acid and malic acid, that a mixture of dye compounds will be obtained due to there being different carboxylic acid reactive groups in the molecule which can attach to the heterocyclic ring. It is also to be noted that for R* groups which are hydroxy-terminated, such as for example lactic acid or citric acid, it is possible for polyester formation to occur via reaction of the lactic acid moiety (or citric acid) with another lactic acid (or citric acid) moiety. In the case of lactic acid polymerisation of two lactic acid molecules therefore the R* group would be CH(CH3)O(CO)CH(CH3)OH. Depending on the reaction conditions therefore, a mixture of dye compounds can be obtained, for example in the case of citric acid, a mixture of one or more of the mono-citrate compounds (there could be two different isomers of these depending on which carboxylic acid group attaches to the heterocyclic ring), bis-citrate compounds (including different structural isomers), and compounds formed from a citric acid polymer.
Without wishing to be bound by theory, it is believed that high fixation values for the reactive dye compounds herein derived from hydroxy carboxylic acids such as citric acid is the result of preferential bonding of the reactive dye to nucleophiles on the fibre vis à vis nucleophiles in solution. Additionally, any hydrolyzed dye may be reactivated by carboxylic acids present in solution.
Preferred reactive dye compounds of the present invention may be represented by the following formula (I): 
wherein:
D is a chromophoric group;
L is a linking moiety selected from NR, N(Cxe2x95x90O)R, N(SO2)R;
R is H or C1-C4 alkyl which can be substituted by halogen, hydroxyl, cyano, C1-C4 alkoxy, C2-C5 alkoxycarbonyl, carboxyl, sulfamoyl, sulfo, sulfato;
Z is a nitrogen-containing heterocycle;
Y is A(CO)R*, A being selected from O or S, R* being selected from (CH2)nSH, (CH2)nNH2, CH(CH3)OH, C(OH)(CH2COOH)2, CH2C(OH)(CO2H)CH2COOH, C(OH)(H)CH2COOH, CH2C(H)(OH)COOH, (CH2)nNHR1, CH2NR1R2, CH2NHNH2, CH2NHOH, CH2SMe, CH(NH2)(CH2)nCOOH, CH(NH2)CH2SMe, CH(NH2)CH2SSCH2CHNH2)COOH, CH(NH2)CH2SO3H, C6H4OH, C(H4COOH, C6H4NH2, C5H4N, (CH2)nC5H4N, (CH2)nSSO3xe2x88x92, (CH2)nxe2x80x94Sxe2x80x94Sxe2x80x94(CH2)n, derivatives of hydroxy carboxylic acid polymerisation, eg. in the case of lactic acid dimerisation R* is CH(CH3)O(CO)CH(CH3)OH, peptide or polypeptide, wherein R1 and R2 is independently selected from C1-C4 alkyl, wherein n is an integer in the range of 1 to 4 wherein within the same molecule n is not necessarily the same integer and where R# corresponds to an amino acid sidechain.
X is selected from Y (i.e. bis-oxy- or bis-thio-carbonyl compounds), thio-derivatives, halogen (preferably fluorine and chlorine), amines, alkoxy groups, carboxylic acid groups, CN, N3, quaternized nitrogen derivatives, Q+, SO2CH2CH2Xxe2x80x2, Lxe2x80x2SO2CH2CH2Xxe2x80x2, wherein Xxe2x80x2 is selected from thio-derivatives, halogen (preferably fluorine and chlorine), amines, alkoxy groups, carboxylic acid groups, CN, N3 and quaternized nitrogen derivatives, Q+, and wherein Lxe2x80x2 is selected from HNR**, wherein R** is selected from C1-C4 alkyl, benzyl, phenyl, especially those derived from para bases and meta bases;
m is 1 or 2 (depending on the Z group, for example m is 1 when Z is triazine and m is 2 when Z is pyrimidine).
Suitable thio-derivatives for use herein include, but are not necessarily limited to groups having the formula SRxe2x80x2 wherein Rxe2x80x2 is selected from H or alkyl or preferably short chain alkyl (preferably less than about 6 carbon atoms), alkanol, alkyl carboxylate, alkylamide, alkylsulphonate, alkyl phosphonate, alkyl thiosulphonate, alkylamine, alkyl thiosulphate, aryl sulphonate, aryl carboxylate, aryl phosphate, aryl amine, cyanates, sulphonates, branched alkyl thio carboxylates, branched alkanol thiols, guanides, alkyl-xcex1-amino-xcex1-carboxylate, (di) thio alkyl esters of glycerol, alkyl thiol alkyl esters of glycerol, alkyl esters, mono thio diesters, thiol alkyl esters of ethylene glycol, alkyl thiol alkyl ester of ethylene glycol and alkyl thiolipoates. Preferably Rxe2x80x2 is selected from alkyl carboxylates, alkanols and alkylamines.
Examples of suitable thio-derivatives include SRxe2x80x2 groups where Rxe2x80x2 is selected from C1-C4 alkyl, (CH2)nCOOH, (CH2)nCONH2, (CH2)nSO3H, (CH2)nCOOM, (CH2)nPO3H, (CH2)nOH, (CH2)nSSO3xe2x88x92, (CH2)nNRxe2x80x32, (CH2)nN+Rxe2x80x33, PhSSO3xe2x88x92, PhSO3H, PhPO3H, PhNRxe2x80x32, PhN+Rxe2x80x33, xe2x80x94CN, SO3xe2x88x92, (CH2)2CH(SH)Rxe2x80x3(CH2)3COOH, xe2x80x94CH2CHOHCH2SH, and 
n is an integer in the range of 1 to 4 wherein within the same molecule n is not necessarily the same integer; and M is a cation of alkaline earth metal, alkali metal, NH4+ or NRxe2x80x33+ and wherein Rxe2x80x3 is C1-C4 alkyl.
Preferred thio-derivatives for use herein have the formula SRxe2x80x2 wherein Rxe2x80x2 is (CH2)nCOOH, (CH2)nOH, and (COOH)CH2CH2(COOH), wherein n is an integer from 1 to 4.
Especially preferred for use herein are thioglycolate (Rxe2x80x2=CH2COOH) thioethanol (Rxe2x80x2=(CH2)2OH) and thiosuccinate (Rxe2x80x2=(COOH)CH2CH2(COOH)), especially thioglycolate.
Suitable quaternized nitrogen derivatives for use herein can be represented by Q+ wherein Q is selected from amines, saturated or unsaturated, substituted or unsubstituted nitrogen containing heterocycles having from about 3 to about 8 ring members and comprising at least one nitrogen heteroatom. Preferred substituents are carboxylates, amides, C1-C4 alkyl and alkyl carboxylates.
Particularly preferred for use herein are Q groups selected from:
NRxe2x80x33, 
(CH3)2Nxe2x80x94NH2;
N(CH3)2CH2COOH (dimethylaminobetaine);
N(CH3)2(CH2)nNH2 
N(CH3)2(CH2)nN+Rxe2x80x33;
N(CH3)2CH2CONH2;
wherein Rxe2x80x3 is C1-C4 alkyl and n is an integer of from 1 to 4.
Particularly preferred quaternized nitrogen derivatives for use herein are nicotinate, diazabicyclooctane (DABCO), dimethylaminobetaine and isonicotinate, especially nicotinate.
The quaternized nitrogen derivative is attached to the nitrogen-containing heterocycle via its tertiary nitrogen atom.
Preferred X groups include Y, SRxe2x80x3, halogen (preferably F or Cl), NRxe2x80x3H, NRxe2x80x32, ORxe2x80x3, COOH, SCN, SSO3, SO3, NR1R2, CN, N3 and quaternized nitrogen derivatives Q+, wherein Rxe2x80x3 is C1-C8 alkyl, or aryl and wherein Q, R1 and R2 are as defined above.
Particularly preferred X groups for use herein are Y, halogen (fluorine and chlorine) and quaternized nitrogen derivatives.
A particularly preferred reactive dye compound of the present invention wherein the O(Cxe2x95x90O)R* group in formula (I) above is derived from citric acid has the following structure Ia 
Another particularly preferred reactive dye compound of the present invention wherein the O(Cxe2x95x90O)R* group is derived from citric acid has the following formula Ib: 
The compounds Ia and Ib above differ due to a different COOH group of the citric acid attaching itself to the heterocyclic group Z.
Other preferred reactive dye compounds of the present invention can be represented by the formula (II): 
wherein B may vary within the same molecule and is a chromophore D as defined above or other organic radical suitable for use in place of a chromophore provided that the reactive dye compound contains at least one chromophore group;
L, Z, X, A, m are the same or different within a single molecule and are as defined hereinabove;
J is selected from S, O, NH, CO2, COS (where in the case of CO2 and COS the carbon atom is attached to the L group and the O or S group respectively is attached to the Z group)
Lxe2x80x2 is a linking group which can be any suitable biradical linking group suitable for use in dye compounds and is preferably selected from xe2x80x94(CH2)nxe2x80x94, xe2x80x94(CH2)nxe2x80x94SO2xe2x80x94(CH2)nxe2x80x94, HN(CH2)nxe2x80x94, xe2x80x94CH(OH)(CH2)nCH(OH)(CH2)m where m=0-20, preferably 0-1, xe2x80x94(CH2)xe2x80x94Sxe2x80x94Sxe2x80x94(CH2)nxe2x80x94, xe2x80x94CH(OH)(CH2)pxe2x80x94, xe2x80x94CH(NHR)(CH2)pxe2x80x94, where R is alkyl or H, and where p=0-20, preferably 1-4, xe2x80x94CH2xe2x80x94C(OH)xe2x80x94CH2COOH or xe2x80x94CH2xe2x80x94C(COOH)(OH)xe2x80x94CH2xe2x80x94, xe2x80x94(CH2)nxe2x80x94Sxe2x80x94(CH2)n, xe2x80x94(CH2)nxe2x80x94(Sxe2x80x94O)xe2x80x94(CH2)n, xe2x80x94(CH2)nO(CH2)n, (CH2)nSe(CH2)nxe2x80x94, xe2x80x94(CH2)nxe2x80x94NRxe2x80x94(CH2)n, where R is alkyl or H, xe2x80x94CHR where R is alkyl or H. Preferably Lxe2x80x2 is xe2x80x94(CH2)nxe2x80x94, xe2x80x94CH2xe2x80x94C(OH)xe2x80x94CH2COOH, xe2x80x94CH(OH)xe2x80x94CH(OH)xe2x80x94, or CHR wherein R is methyl.
Polyfunctional carboxylic acids with various nucleophilic substituents can be used to crosslink a number of dye molecules, i.e. tris, tetrakis compounds can also be prepared using suitable starting materials and using suitable reaction conditions.
Another preferred reactive dye compound according to the present invention can be represented by compounds of the formula (III): 
wherein each of D, L, Z, Y, X and m are the same or different and are as defined above.
Heterocyclic rings containing one or more oxy- or thio-carbonyl substituents can be used as a template to build dentritic reactive coloured polymers according to the invention.
In the above formulations it is to be noted that within each compound each of the defined groups may be the same or different. For example, in formula (III), one of the Z groups may be pyrimidine and the other Z group may be triazine.
The present invention furthermore relates to processes for the preparation of dyes herein. In general, dyes having the formula (I) can be prepared by reacting suitable precursors of the dye of formula (I) with one another, at least one of which contains a group Dxe2x80x94Lxe2x80x94Z, wherein D, L and Z are as defined above, and at least one of which contains a Y group (wherein Y is as defined above) and at least one of which contains an X group. It will be understood by those skilled in the art that in the case where X is halogen, then the halogen is part of the Z group in the starting materials e.g. dichlorotriazine.
For example, dye compounds of the invention having a formula (I) wherein Z is a triazine heterocycle can be prepared by reacting one mole of dichlorotriazine dye, such as those commercially available from BASF under the trade name Procion MX (RTM), with one mole of a suitable reactant containing a Y group and then reacting the intermediate dye compounds obtained with one mole of a suitable reactant containing an X group. It will be understood by those skilled in the art that when X is halogen, then the halogen is part of the starting material containing the Z group, e.g. dichlorotriazine, and no separate reaction with a reactant containing an X group needs to be carried out. It will also be understood by those skilled in the art that in the case where X is equal to Y (i.e. bis-oxy carbonyl compounds) then one mole of dichlorotriazine dye can be reacted with two moles of a suitable reactant containing a Y group.
Dye compounds of the invention having a formula (I) wherein Z is a pyrimidine heterocycle can be prepared by reacting a difluoromonochloro pyrimidine dyes such as those commercially available from Clariant under the trade names Drimalan F (RTM) and Drimarene R or K (RTM), or a trichloropyrimidine dyes such as those commercially available from Clariant under the trade name Drimarene X, with a suitable reactant containing a Y group and then reacting the intermediate dye obtained with a suitable reactant containing an X group. As discussed above for triazines, it will be understood by those skilled in the art that when X is halogen, then the halogen is part of the starting material containing the Z group, e.g. difluoromonochloropyrimidine or trichloropyrimidine, and no separate reaction with a reactant containing an X group needs to be carried out. It will also be understood by those skilled in the art that in the case where X is equal to Y (i.e. bis-oxy carbonyl compounds) then one mole of difluoromonochloro pyrimidine dye can be reacted with two moles of a suitable reactant containing a Y group.
Due to the assymmetric nature of the pyrimidine heterocycle, dye compounds of the invention having a formula (I) wherein Z is a pyrimidine heterocycle can also be prepared by reacting a difluoromonochloropyrimidine dye such as those commercially available from Clariant under the tradenames Drimalan F (RTM) and Drimarene R or K (RTM), or a trichloropyrimidine dye such as those commercially available from Clariant under the trade name Drimarene X, with a suitable reactant containing a Y group and then reacting the intermediate dye obtained with a suitable reactant containing an Xxe2x80x2 group.
Dye compounds of the invention having a formula (I) wherein Z is a quinoxaline heterocycle can be prepared by reacting a dichloroquinoxaline dye such as those commercially available from Dystar under the tradename Levafix E (RTM), with a suitable reactant containing a Y group and then reacting the intermediate dye obtained with a suitable reactant containing an X group. It will be understood by those skilled in the art that when X is halogen, then the halogen is part of the starting material containing the Z group, e.g. dichloroquinoxaline, and no separate reaction with a reactant containing an X group needs to be carried out. It will also be understood by those skilled in the art that in the case where X is equal to Y (bis-oxy-carbonyl compounds) then one mole of dichloroquinoxaline dye can be reacted with two moles of a suitable reactant containing a Y group.
In order to ensure that the reactant containing the Y group bonds to the Z group via the oxy- or thio-carbonyl group it is preferable to carry out the reaction under acidic conditions, preferably at a pH of from about 1 to about 6.5, preferably from about 3 to about 5. It is also important for the reactant containing the Y group to be added to the Z group slowly, preferably over several hours, preferably 1-5 hours, more preferably 1-3 hours.
In general, dyes having the formulae (II) and (III) can be prepared by using the same general chemistry as for dyes of formula (I) by reacting together suitable starting materials, and as exemplified below in Examples 11, 12, 13, 14, 17, 18 and 19.
Hence according to another aspect of the present invention there is provided the product obtainable by any of the processes detailed herein. In particular there is provided herein the product obtainable by a process wherein the process comprises the steps of reacting a first starting material (preferably one mole) with a second starting material (preferably one mole), the first starting material comprising at least one chromophore, at least one nitrogen-containing heterocycle and a linking group to link each chromophore to each nitrogen-containing heterocycle (for example a Procion MX dye), the second starting material comprising an oxy- or thio-carbonyl group (for example citric acid).
It is preferable that the reaction is carried out at a pH of between about 2 to about 8, preferably about 3 to about 5. It is also preferably that the second starting material is added to the first starting material slowly and dropwise, preferably over several hours, preferably over 1 to 5 hours, more preferably over 1-3 hours.
The dye compounds herein are suitable for dyeing and printing a wide variety of substrates, such as silk, leather, wool, polyamide fibres and polyurethanes, keratin fibres such as hair, and in particular cellulosic materials, such as the natural cellulose fibres, cotton, linen, hemp and the like, paper, and also cellulose itself and regenerated cellulose, wood, and hydroxyl-containing fibres contained in blend fabrics, for example blends of cotton with polyester or polyamide fibres.
The dye compounds of the present invention can be applied and fixed to the substrate in various ways, in particular in the form of a solid mixture, aqueous dye solutions and printing pastes. Thus according to the present invention there is provided a dye composition comprising one or more of the dye compounds described herein together with any carrier material suitable for use in a dye composition.
Preferred dye compositions herein comprise an acidic buffer material. Any acidic buffer suitable for use in reactive dye compositions can be used herein. An example of a suitable buffer is a mixed phosphate buffer.
When the dye composition herein is in the form of a paste a preferred ingredient is a thickening agent. Any suitable thickening agents suitable for use in reactive dye compositions can be used herein.
When the dye composition is in the form of an aqueous solution or aqueous gel/paste, the dye composition preferably has a pH of from about 2 to about 8.
The dyeing and printing processes which can be used with the dyes herein are conventional processes which are well known and which have been widely described in the technical and patent literature. The dye compounds herein are suitable for dyeing cotton both by the exhaust method (long liquor) and also by various pad-dyeing methods, whereby the goods are impregnated with aqueous, salt-containing or salt-free dye solutions and the dye is fixed after an alkali treatment or in the presence of alkali, if appropriate with the application of heat. The dye compounds herein are also suitable for the cold pad-batch method, in which the dye together with the alkali is applied at the pad-mangle melting point and then fixed by several hours of storage at room temperature. After fixing, the dyeings are thoroughly rinsed with cold and hot water, if appropriate with the addition of an agent acting as a dispersant and promoting the diffusion of the non-fixed portions. The dyes of the present invention are also suitable for use in a number of other processes such as pad-steam and pad-bake and the like.
Thus in accordance with another aspect of the present invention there is provided a use of the reactive dyes of the present invention for dyeing and printing substrates such as cotton, wool, nylon, silk, keratin, hair, leather, paper and the like. The compounds herein can be used in methods of dyeing all of the substrates listed above by applying an aqueous solution of one or more of the reactive dyes of the present invention to the substrate to be dyed under suitable conditions of pH and temperature.